> Chromebook sold by various manufacturers. But it comes with more limitations, and requires users to be totally comfortable — I’m not

Tell that to the grandma. Believe me, I'm no Google Chrome fan, but Google Chrome OS is what Linux would never be. It is a completely different target audience. Microsoft, and Apple eventually, should be worried (and they are most likely worried - given the number of cheap Windows 10 laptops I have been seeing lately).